(a) Technical Field
This disclosure relates to a head fixing mechanism of a drum, and specifically relates to a head fixing mechanism provided in a drum including a head that covers an opening of a trunk portion and a hoop that holds the head onto the trunk portion.
(b) Description of the Related Art
In the past, a drum has included a head that covers an opening of a trunk portion, a hoop that holds the head onto the trunk portion, and a head fixing mechanism provided in the trunk portion. The head fixing mechanism presses the hoop against the trunk portion using a screw member such as a bolt. A person who tunes such drum adjusts a force that presses the hoop against the trunk portion by tightening or loosening the screw member of the head fixing mechanism, and adjusts the tension of the head.
When the drum is played, the drum vibrates as a whole and the screw member of the head fixing mechanism may be loosened due to the vibration, and thus the drum may get out of tune.
Consequently, a head adjustment apparatus is proposed in which a washer with rubber is provided between a lower surface of a head portion of the bolt and the hoop, and the washer with rubber is constituted by a rubber elastic body and a bowl-shaped cover of which external shape covers the outer circumference of the rubber elastic body (Japanese Unexamined Patent Application Publication No. 2006-58849).
According to the head adjustment apparatus, since vibration generated by the playing of the drum can be absorbed by the elastic body, it is possible to prevent the drum from getting out of tune due to the loosening of the bolt.
However, since the head adjustment apparatus disclosed in Japanese Unexamined Patent Application Publication No. 2006-58849 is provided with the washer with rubber in addition to the bolt, the number of parts to assemble are increased, and thus assembly processes of the drum may be complicated. In addition, when the head adjustment apparatus is used for a long period of time, rubber of the washer may be hardened due to aging degradation, and thus may not play the role of absorbing vibration.